Self-Reference Emerges Earlier than Emotion during an Implicit Self-Referential Emotion Processing Task: Event-Related Potential Evidence

Abstract

Self-referential emotion refers to the process of evaluating emotional stimuli with respect to the self. Processes indicative of a self-positivity bias are reflected in electroencephalogram (EEG) signals at ~400 ms when the task does not require a discrimination of self from other. However, when distinguishing between self-referential and other-referential emotions is required, previous studies have shown inconsistent temporal dynamics of EEG signals in slightly different tasks. Based on the observation of early self–other discrimination, we hypothesized that self would be rapidly activated in the early stage to modulate emotional processing in the late stage during an implicit self-referential emotion. To test this hypothesis, we employed an implicit task in which participants were asked to judge the order of Chinese characters of trait adjectives preceded by a self (“I”) or other pronoun (“He” or “She”). This study aimed to explore the difference of social-related emotional evaluation from self-reference; the other pronoun was not defined to a specific person, rather it referred to the general concept. Sixteen healthy Chinese subjects participated in the experiment. Event-related potentials (ERPs) showed that there were self-other discrimination effects in the N1 (80–110 ms) and P1 (170–200 ms) components in the anterior brain. The emotional valence was discriminated in the later component of N2 (220–250 ms). The interaction between self-reference and emotional valence occurred during the late positive potential (LPP; 400–500 ms). Moreover, there was a positive correlation between response time (RT) and N1 in the self-reference condition based on the positive-negative contrast, suggesting a modulatory effect of the self-positivity bias. The results indicate that self-reference emerges earlier than emotion and then combines with emotional processing in an implicit task. The findings extend the view that the self plays a highly integrated and modulated role in self-referential emotion processing.

Event-related potential and behavioural differences in affective self-referential processing in long-term meditators versus controls

“…Past studies investigating self-related affect in healthy groups have been ambiguous with regard to whether there should be a positivity (towards pleasant words) and negativity (towards unpleasant words) bias in the LPP response with some studies showing higher LPPs for pleasant compared to unpleasant self-referential words (e.g., Auerbach et al, 2015;Shestyuk & Deldin, 2010;Watson et al, 2007), while others show a self-related negativity bias of the kind we observed (e.g., Bernat, Bunce, & Shevrin, 2001;Fields & Kuperberg, 2012;Zhou et al, 2017).…”

“…However, the findings are mixed. The P200 and LPP have been found to be both higher for pleasant compared to unpleasant self-referential words (Auerbach et al, 2015;Shestyuk & Deldin, 2010;Watson et al, 2007) as well as higher for 6 ERP of affective self-reference in meditators unpleasant compared to pleasant ones (Fields & Kuperberg, 2012;Zhou et al, 2017) in separate studies. ERP differences between pleasant and unpleasant words in the SRET have been used to identify brain patterns that differentiate healthy and clinical populations.…”

“…Only one previous study has been conducted on a middle-to-old age group (mean = 43 years), which also showed a negativity bias (Zhou et al, 2017).…”

Event-related Potential and Behavioural Differences in Affective Self-Referential Processing in Long-term Meditators versus Controls

“…LPPs for pleasant compared to unpleasant self-referential words (e.g., Auerbach et al, 2015;Shestyuk & Deldin, 2010;Watson et al, 2007), while others show a self-related negativity bias of the kind we observed (e.g., Bernat, Bunce, & Shevrin, 2001;Fields & Kuperberg, 2012;Zhou et al, 2017).…”

“…However, the findings are mixed. The P200 and LPP have been found to be both higher for pleasant compared to unpleasant self-referential words (Auerbach et al, 2015;Shestyuk & Deldin, 2010;Watson et al, 2007) as well as higher for unpleasant compared to pleasant ones (Fields & Kuperberg, 2012;Zhou et al, 2017) in separate studies. ERP differences between pleasant and unpleasant words in the SRET have been used to identify brain patterns that differentiate healthy and clinical populations.…”